Scalar Dark Matter with CERN-LEP data and $Z'$ search at the LHC in an $U(1)'$ Model

TL;DR

This paper explores a nonuniversal $U(1)'$ extension of the standard model proposing a scalar dark matter candidate, analyzing constraints from CERN-LEP and LHC data, and identifying viable dark matter mass ranges and model parameters.

Contribution

It introduces a scalar dark matter candidate within a $U(1)'$ model and derives new constraints on its mass and the gauge coupling using collider and cosmological data.

Findings

Dark matter mass constrained to 70 GeV in higgsphobic scenario

Lower limit of $Z'$ mass at 3 TeV from LHC data

Viable dark matter masses range from 1.3 GeV to 125 GeV

Abstract

In the framework of an nonuniversal $U(1)'$ extension of the standard model, we propose an scalar candidate for cold dark matter which exhibits interactions with ordinary matter through Higgs and gauge bosons. Using limits from low energy observables, we find constraints on the new physics parameters of the model associated to the extra abelian symmetry, in particular, the mass of the additional neutral gauge boson $Z'$ and the new gauge coupling constant. We found that for the lower experimental limit $M_{Z'}=3$ TeV constrained by direct research at LHC, the ratio between the $U(1)'$ and $SU(2)_L$ gauge coupling constants is around $0.4$. Taking into account this limit and the observable relic density of the Universe, we search for new constraints on the mass of the dark matter particle of the model. We found that for a higgsphobic model, the mass of the scalar dark matter must be $M_{\sigma}=70$ GeV. We also found different kinematical threshold and resonances that enhance the dispersion of dark matter into ordinary matter for different regions of the space of parameters of the model, obtaining masses as low as $1.3$ GeV and as large as $125$ GeV with not allowed intermediate regions due to resonances.